platform: add rcc register definitions for stm32f4
fixed: wrong file(stm32f429/registers.h) include in stm32f4/rcc.h, fixed it
platform: Move gpio functions to gpio-$(STM32_VARIANT).c for stm32 variants
platform: Add conditional build in rcc.c for different stm32 series
platform: Add gpio functions for stm32f1x
platform: Add rcc functions for stm32f1x
platform: Add stm32-p103 support
	qemu simulation enabled
travis: update defconfig of discoveryf4 and discoveryf429
travis: travis now will check stm32p103
Merge pull request #102 from slpbaby/stm32-p103

platform: add stm32-p103 support, which is vital for QEMU modeling